Blood is routinely irradiated in hospitals and blood banks to prevent against the fatal transfusion associated graft-versus-host disease (GVHD) in certain at risk patients. A dose of 25 Gy is delivered to the blood bag with no part receiving less than 15 Gy. Most blood irradiators in existence today are based on radioactive isotopes, mainly Cesium-137 and in some cases Cobalt- 60. These two isotopes constitute the most dangerous and most prevalent of all radioisotopes in the NRC inventory. The NRC strongly recommends replacement of these isotopes by competent technology such that healthcare is not compromised. X-ray is the only other technology cleared by the FDA for this application. However the current x-ray system available in the market today is unable to meet the performance of the radioisotope based systems. This is due to the fact that the x-ray tube used is not tailored to the application at hand. Our company has developed a novel Flat Panel X-ray Source (FPXS) that offers unique advantages in sterilization applications due to its construction. Unlike in conventional x-ray systems where x-rays are generated on a small spot on the angled anode, our design produces x-rays over a much broader area on a flat anode surface. The x-ray flux generated exits over a wide angle (~180[unreadable]) thus providing tremendous advantages in terms of power efficiency and thermal management. The primary goal of this proposal is to develop and commercialize Stellarray's FPXS based blood irradiators for GVHD prevention. Studies will be conducted by our collaborator, Dr. Suresh Pillai at Texas A&M University to determine the efficacy of the low energy x-ray irradiation on leukocyte inactivation and RBC function compared to gamma irradiation. Another goal to be achieved is to study the effects of irradiation on platelets and determine the doses needed to extend their shelf-life. Our hypothesis is that irradiation can inactivate the bacterial and viral contamination rates in platelet products and thus extend their shelf-life. PUBLIC HEALTH RELEVANCE: Blood irradiation is the only approved method to prevent against transfusion associated graft versus- host disease which can be a life-threatening consequence of transfusing blood into certain at-risk patients. We propose the development of x-ray blood irradiators based on our novel flat panel x-ray sources (FPXS) that offer unique capabilities not available with currently available systems. The FPXS based systems will provide compact, reliable and high throughput capabilities to blood transfusion facilities and enable them to meet the increasing demand for irradiated blood products.